1. Field of the Invention
The present invention relates in general to apparatus for detecting the presence of a warm-blooded mammal in an enclosed location and in particular to apparatus for detecting the presence of a bird or birds in a birdhouse.
2. Description of Related Art
Ornithologist and bird lovers in general are interested in knowing when birds have occupied a birdhouse and they spend many hours watching birds come and go and are interested in knowing when the birds are sitting on the nest and the like. It would be of assistance if the presence of the bird could cause a visual or audible indication so that an individual would know that the bird has entered the birdhouse or is on the nest.